JPH10192692A - Gas-liquid contact reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform a gas-liquid contact reaction simply, inexpensively and highly efficiently. SOLUTION: In a gas-liquid contact reactor blowing reactive raw material gas into a reactive raw material liquid 23 to perform chemical reaction, a gas return member 36 having a rising passage 48 collecting a gas product to allow the same to pass and a falling passage 50 communicating with the rising passage to allow the gas product to flow into the reactive raw material liquid formed thereto is provided in a reaction column 32 storing the reactive raw material liquid. By this constitution, heat energy necessary for a gas-liquid contact reaction can be conserved and the production efficiency of the gas product is enhanced and an output can be increased and the purifying degree of the gas product can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reactor used for a gas-liquid contact reaction for reacting a liquid and a gas, and more particularly, to a reactor for producing hydrogen sulfide (H ₂ S) by reacting sulfur with hydrogen. Things.

[0002]

2. Description of the Related Art A method for producing hydrogen sulfide by reacting sulfur and hydrogen in a gas phase is well known. However, when reacting sulfur and hydrogen, the temperature rise due to reaction heat is large. Temperature control of the reactor is required. Heretofore, as a countermeasure, a method has been known in which a large excess of hydrogen and a small amount of sulfur are used to limit the reaction amount of the two to suppress the temperature rise. However, in this method, not only is the utilization rate of hydrogen low, but the size of the apparatus per unit of hydrogen sulfide production increases, and excessive equipment such as a large amount of hydrogen circulation and the absorption and regeneration steps involved. Is required, and there is a problem that the manufacturing apparatus becomes large and expensive. Therefore, Tokiko Sho 46-
No. 5572 discloses that two or more gas-phase reaction chambers are connected in series, and sulfur is introduced into a sulfur introduction vaporization chamber provided at the inlet of each reaction chamber while passing hydrogen heated to a temperature sufficient to vaporize sulfur. A method of reacting by split supply is shown. However, in this method, only about 1 mol% of S ₈ (sulfur vapor) can be reacted to suppress the temperature rise to within 100 ° C. in one step. It is necessary and uneconomical.

[0003] Also, Japanese Patent Publication No. Hei 5-11046 discloses that
A method for producing hydrogen sulfide by reacting sulfur in a liquid phase with hydrogen gas is disclosed. This method will be described with reference to FIG. In this method, first, the liquid sulfur 2 is heated to a predetermined temperature range of 250 ° C. or higher by the temperature controller 4 in the reaction tower 1. Then, a hydrogen gas is supplied into the reaction tower 1 through the supply line 3, and the hydrogen gas is blown out into the liquid sulfur 2 from a nozzle 5 disposed at a lower part in the reaction tower 1. Reaction tower 1
The hydrogen gas blown into the reactor comes into contact with the liquid sulfur 2 in the reaction tower 1 to generate hydrogen sulfide gas. The generated hydrogen sulfide gas is sent from the reaction tower 1 to the condensation separator 7 through the line 6. The gas flowing out of the reaction tower 1 is accompanied by sulfur vapor, unreacted hydrogen and the like in addition to the hydrogen sulfide gas. In the condensing separator 7, the gas sent through the line 6 is cooled, and the contaminated sulfur vapor is separated and recovered. Also,
A part of the gas flowing out of the reaction tower 1 is sent to a hydrogenation reactor 8, where sulfur vapor and hydrogen are brought into gas phase contact reaction to generate hydrogen sulfide. Further, the separation gas taken out from the condensation separator 7 by the line 9 may still contain unreacted hydrogen and sulfur vapor in addition to hydrogen sulfide. The reaction is further refined to reduce sulfur vapor and increase the amount of hydrogen sulfide.

[0004]

Incidentally, in the above-mentioned reaction tower 1, even in the gas phase section 16, sulfur vapor and hydrogen are in gas phase contact reaction, and the calorific value due to the reaction is large. It is not easy to control the temperature of the liquid-phase sulfur 2 without taking into account the above, and it is difficult to optimize the heat balance.
In order to maintain the temperature of the liquid sulfur 2 at a predetermined temperature, not only heating or cooling by the temperature controller 4 but also a control device such as a cooling jacket 18 is provided so as to cover the periphery of the gas phase section 16. Although it is conceivable to cool 16, the device becomes complicated. There is also a need for more efficient production of hydrogen sulfide. Also, Japanese Patent Application Laid-Open No. 6-2853
No. 64, as shown in FIG. 5, a partition 21 is provided in a reaction tower 20 for storing a reaction raw material liquid 23, and a reaction raw material gas is blown from a gas blowing nozzle 22 provided below.
Although a method of increasing the efficiency of gas-liquid contact by circulating and flowing is disclosed, even with this method, the above-described disadvantages are likely to occur. Furthermore, Japanese Patent Publication No. 5-67562 discloses that an internal reflux device for refluxing sulfur vapor in a gas phase is provided to cool and liquefy the sulfur vapor, thereby suppressing the reaction in the gas phase and reducing the calorific value. Although it is shown that the concentration is reduced and the concentration of hydrogen sulfide is increased by removing sulfur vapor, it is not always satisfactory in increasing the production amount. The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to provide a reactor for performing a gas-liquid contact reaction easily, inexpensively, and efficiently.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies on the reaction of generating hydrogen sulfide by blowing hydrogen gas into liquid sulfur. As a result, the following two reactions also occur in liquid sulfur. I found that I was the subject. S ₆ (g) + 6H ₂ → 6H ₂ S + 53 kcal / mol S ₆ ... (1) S ₈ (g) + 8H ₂ → 8H ₂ S + 62 kcal / mol S ₈ ... (2) Further, the latent heat of vaporization of liquid sulfur is 68 kcal / kgS (420
° C) and the reaction rate were taken into consideration comprehensively, and the present invention was completed. That is, in the gas-liquid contact reactor of the present invention, in a gas-liquid contact reactor in which a reaction raw material gas is blown into a reaction raw material liquid to perform a chemical reaction, a gas product is collected in a reaction tower for storing the reaction raw material liquid. And a gas returning body formed with a descending passage communicating with the rising passage and allowing the gaseous product to flow out into the reaction raw material liquid. . At this time, the gas returning body has an outer tube having an upper end closed and a lower end opened into the reaction raw material liquid, and an inner tube arranged in the outer tube. It is preferable that an ascending flow path is formed in the inner pipe and a descending flow path is formed in a gap between the inner pipe and the outer pipe.

Further, it is preferable to provide a gas collecting body whose diameter is enlarged downward at the lower end of the rising channel. Further, a plurality of the gas returning bodies may be provided. A gas-liquid contact reactor according to claim 4 is a gas-liquid contact reactor in which a reaction material gas is blown into a reaction material liquid to perform a chemical reaction. 6. A cylindrical structure comprising an outer cylinder having a lower end and an open lower end, and having a vertical gas flow path communicating with the inside thereof, wherein the cylindrical structure is provided in the liquid phase portion, wherein: The gas-liquid contact reactor is a gas-liquid contact reactor in which a reactant gas is blown into a reactant liquid to carry out a chemical reaction. The gas-liquid contact reactor has a vertical gas passage communicating with the inside thereof, and a lower end of the gas passage. And a structure in which the other gas flow path is opened downward is provided in the liquid phase portion. These reactors are particularly suitable for producing hydrogen sulfide by blowing hydrogen gas into liquid sulfur.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to FIG. In the reactor 30 shown in FIG.
A liquid supply pipe 34 for supplying the reaction raw material liquid 23 to a lower portion of the reaction tower 32, a gas introduction means for supplying a reaction raw material gas, a gas return body 36 disposed in the reaction tower 32, and a reactor outlet 35. The configuration is schematically provided. The gas introduction means includes a pipe 39 for supplying the reactant gas, and the pipe 39.
And a nozzle 38 positioned in the reaction raw material liquid 23 stored in the reaction tower 32.
Compressor (not shown) from the gas tank connected to 9
The reaction raw material gas supplied by the nozzle blows out from the nozzle 38.

The illustrated gas returning body 36 is provided with a cylindrical outer tube (outer tube) 40 whose upper end is closed and whose lower end is open, and is provided inside the outer tube 40, and both upper and lower ends are open. And an upper end 44 of the inner tube 42 and an outer tube 40.
A gap 45 is formed between the inner tube 42 and the upper wall 46.
The ascending flow path 48, which is the internal space of the pipe, and the descending flow path 50, which is a space formed between the inner pipe body 42 and the outer pipe body 40, communicate with each other through a gap 45. At this time, at least the descending flow path 50
The lower end 52 of the reaction raw material liquid (liquid phase portion) 2
3 is required. In addition, gas returning body 3
6 is disposed inside the reaction tower 32 so as to form a gap 54 with the inner wall 33 of the reaction tower 32. Also, the gas returning body 36
May be arranged so that a part thereof is exposed to the gas phase portion 16. However, in order to enhance the heat exchange effect described later, as shown in FIG. Is preferred.

The number of the gas returning bodies 36 is not limited to one. As shown in FIG. 3, a plurality of, for example, three or seven gas returning bodies 36, 36,. It may be provided in one reaction tower 32.

[0010] Like the inner wall of the reaction tower 32, the material of the gas returning body 36 is not particularly limited as long as it is not corroded by a reaction raw material liquid, a reaction raw material gas, a reaction product and the like and has heat resistance. However, in order to enhance the heat exchange effect, it is preferable to use a material having a high thermal conductivity. For example, austenitic stainless steel may be used. Further, in the illustrated example, a gas collector 56 whose diameter is expanded downward is provided at the lower end of the inner tube 42 so as to easily collect the gas product generated by the gas-liquid contact reaction. Furthermore, in the illustrated reactor, the reaction raw material liquid 23
Inside, above the nozzle 38, a temperature controller 58 for heating or cooling the reaction raw material liquid 23 is provided. For example, an electric heater or the like can be applied to the temperature controller 58.
Reference numeral 60 denotes a manhole used for maintenance or the like.

To use this reactor 30, first, a reaction raw material liquid is supplied into a reaction tower 32 from a liquid supply pipe 34,
To store. Then, the reaction raw material liquid 23 is heated to a predetermined temperature by the temperature controller 58. Then, the reaction raw material gas sent through the pipe 39 is blown out from the nozzle 38 to cause a gas-liquid contact reaction between the reaction raw material liquid and the reaction raw material gas to generate a gas product. Since the gaseous product rises in the reaction raw material liquid 23, the gaseous product is collected by the gas collector 56 and is raised in the rising flow path 48 as it is. At this time, in addition to the gaseous products generated by the gas-liquid contact reaction, the reaction raw material gas and the vapor of the reaction raw material liquid are also collected by the gas collector 56 and rise in the rising flow path 48. These mixed gases are sent upward by a gas product, a reactant gas or a reactant liquid vapor generated one after another.
0, flows out from the lower end 52 of the descending flow path 50 into the reaction raw material liquid 23, and returns. During this time, a gaseous product is also generated by a gas phase reaction between the reactant gas and the vapor of the reactant liquid in the ascending flow path 48 or the descending flow path 50.
Thereafter, the gaseous product returned into the reaction raw material liquid 23 rises through the gap 54 between the outer tube 40 and the inner wall 33 of the reaction tower 32, and is sent to the gas phase section 16, and then the reactor outlet From 35 is sent to the next process.

With such a reactor, the gas recirculation body 3
The heat energy of the heat generated by the gas phase reaction in the outer tube 4
0 and is released to the reaction raw material liquid 23, and the high-temperature gaseous product exits the downflow channel 50 and passes through the reaction raw material liquid 23, so that heat is generated between the gaseous product and the reaction raw material liquid 23. Exchange occurs, the gaseous product is cooled, and the temperature of the reaction raw material liquid 23 is raised. Therefore, the amount of heating by the temperature controller 58 is supplemented. In addition, if the evaporation amount of the reaction raw material liquid increases,
Since the calorific value in the gas phase reaction also increases, if this is reduced,
The latent heat of vaporization associated with the evaporation of the reactant liquid can be covered, but when the vapor of the reactant liquid is reduced or the gas phase reaction is reduced due to deterioration of the heat balance, the heating temperature by the temperature controller 58 is reduced. Should be raised. In addition, since a gas phase reaction is also caused in the gas returning body 36, the product can be produced in a high concentration in a short time. Therefore, with this reactor, the desired product can be obtained at a high concentration without a simple and large-sized or expensive apparatus, and a catalyst is not necessarily required, so that maintenance and the like are easy and economical. It is also a target. In addition, conventionally, in order to increase the degree of purification of the gaseous product or to prevent a high temperature due to the occurrence of a gas phase reaction, the reaction raw material liquid is not evaporated as much as possible. It actively utilizes the gas phase reaction by the liquid, taking into account the gas product and the heat generated by the gas phase reaction.The heat generated by the gas phase reaction is removed by heat exchange with the reaction raw material liquid. The heat energy is used for the latent heat of evaporation of the reaction material liquid and for heating the reaction material liquid, so that the energy required for heating the reaction material liquid can be saved.

In the example based on FIG. 1 described above, the gas returning member 36 is schematically constituted by an inner tube (inner tube) 42 and an outer tube (outer tube) 40 covering the same. The return body is not limited to this. For example, as shown in FIG. 2, an inner pipe 42 forming an ascending flow path 48, and a descending flow path 51 spirally descending around the inner pipe 42. May be roughly constituted by a structure having the outer tube body 41 forming the above. 2, the surface area of the gas returning body 37 in contact with the reaction raw material liquid 23 can be increased, so that the heat exchange efficiency between the gas returning body 37 and the reaction raw material liquid 23 is further improved. be able to.

The above-mentioned reactor is provided with a reaction raw material liquid to be applied,
The reaction raw material gas and reaction product are not particularly limited, but production of hydrogen sulfide by a gas-liquid contact reaction between liquid sulfur and hydrogen gas is preferred. In the case of the production of hydrogen sulfide, first, liquid sulfur is supplied into the reaction tower 32 from the liquid supply pipe 34 and stored. Then, the liquid sulfur is heated to a predetermined temperature by the temperature controller 58. Here, the predetermined temperature is 400 to 48.
Preferably it is 0 ° C. The reaction pressure (gauge pressure) is preferably from 0.3 to 30 kg / cm ² G, and
g / cm ² G is more preferable. Then, the hydrogen gas sent through the pipe 39 is blown out from the nozzle 38,
A gas-liquid contact reaction between liquid sulfur and hydrogen gas occurs. As the hydrogen gas, for example, steam reforming hydrogen such as LPG and naphtha, electrolytic hydrogen, and hydrogen recovered from another plant can be used.

The hydrogen sulfide generated by the gas-liquid contact reaction that rises in the liquid sulfur 23 is collected by the gas collector 56 together with hydrogen gas, sulfur vapor, etc.
Rises inside. Then, these mixed gases in the ascending flow path 48 are sent upward by a mixed gas containing generated hydrogen sulfide generated one after another, and then descend in the descending flow path 50, and the liquid sulfur 23 Spilled into and returned. Further, the hydrogen gas and the sulfur vapor accompanying the hydrogen sulfide undergo a gas phase reaction in the ascending flow path 48 and the descending flow path 50 to generate hydrogen sulfide. Hydrogen sulfide due to this gas phase reaction is
0 is returned into the liquid sulfur 23 from the lower end. Then, both the hydrogen sulfide by the gas-liquid contact reaction and the hydrogen sulfide by the gas phase reaction rise inside the liquid sulfur through the outside of the gas recirculation body 36 and are sent from the gas phase part 16 to the next step through the reactor outlet 35. Be paid. Therefore, in addition to the production of hydrogen sulfide in the liquid phase, hydrogen gas and sulfur vapor that have not undergone a gas-liquid contact reaction react in the gas recirculation body to produce hydrogen sulfide, so that hydrogen sulfide can be produced with high efficiency. In addition, the production volume can be increased, and the concentration of hydrogen sulfide in the collected gas is high, and the amount of hydrogen gas and sulfur vapor is small, so it is possible to reduce the number of condensers and hydrogenation reactors in the next and subsequent steps. it can.
The catalyst is not necessarily required as long as the reaction proceeds sufficiently, but it is also possible to apply the catalyst in a gas phase and / or a liquid phase as appropriate.

[0016]

EXAMPLE Using the reactor shown in FIG. 1, 1.85 kg · mol / hr of liquid sulfur was supplied into the reaction tower 32, and 3.7 kg · of hydrogen gas was supplied.
The supply of mol / hr was continued, and the amount of electric heat required for the hydrogen sulfide concentration in the gas phase 16 to reach 45 vol% was measured by a sensor provided at the top of the reaction tower 32. The gas-liquid contact reaction temperature was set at 420 ° C. by the temperature controller 58, and no catalyst was used. In addition, as a comparative example, hydrogen sulfide was produced by performing a gas-liquid reaction between liquid sulfur and hydrogen gas using the same reactor except that no gas returning body was used. As a result, in the reactor of this example using the gas recirculation body, when the amount of electric heat required for the hydrogen sulfide concentration to be 45 vol% is 100, the hydrogen sulfide concentration is 45 vol% in the reactor of the comparative example. The amount of electric heat required for this is 302, and in the case of the present embodiment, the external energy required for heating the liquid sulfur could be reduced to about 1/3. Further, in the reactor of the present example, heat removal of the gas phase portion was unnecessary, and further energy saving was achieved.

[0017]

According to the present invention, a special structure for performing a gas phase reaction is provided in a liquid phase portion for performing a gas-liquid contact reaction, and the heat of reaction in the gas phase portion is effectively used as a part of a heat source in the liquid phase portion. By utilizing, the heating energy required for the gas-liquid contact reaction can be reduced, the production efficiency of the gas product can be increased, the production amount can be increased, and the purification degree of the gas product can be increased. You can also. In addition, heat generated by the gas phase reaction can be effectively removed. In particular, the thermal balance is excellent, the thermal utility is simple, and the temperature control can be simple and inexpensive. Also, there is no need to use a large excess of hydrogen,
The amount of hydrogen used for the production of hydrogen sulfide can be reduced, and the equipment is simple and does not increase in size. It is possible and economical.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an embodiment of the present invention.

FIG. 2 is a side sectional view showing an embodiment of the present invention.

FIG. 3 is a side sectional view showing one embodiment of the present invention.

FIG. 4 is a schematic configuration diagram showing a conventional reaction method.

FIG. 5 is a side sectional view showing a conventional reactor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reaction tower 2 Liquid sulfur 20 Reaction tower 23 Reaction raw material liquid 30 Reactor 32 Reaction tower 36 Gas returning body 37 Gas returning body 40 Outer pipe 41 Outer pipe 42 Inner pipe 48 Up flow path 50 Down flow path 51 Down flow Road

Claims (7)

[Claims] 1. A gas-liquid contact reactor for blowing a reaction raw material gas into a reaction raw material liquid to carry out a chemical reaction, wherein an ascending flow path for collecting and passing gaseous products in a reaction tower for storing the reaction raw material liquid. A gas-returning body formed with a downward flow passage communicating with the upward flow passage and allowing a gaseous product to flow into the reaction raw material liquid. 2. The gas returning body has an outer tube having an upper end closed and a lower end opened into a reaction raw material liquid, and an inner tube disposed in the outer tube. 2. The gas-liquid contact reactor according to claim 1, wherein an ascending flow path is formed inside the inner pipe, and a descending flow path is formed in a gap between the inner pipe and the outer pipe. 3. The gas-liquid contact reactor according to claim 1, wherein a gas collector whose diameter is increased downward is provided at a lower end of the ascending flow path. 4. A gas-liquid contact reactor in which a reactant gas is blown into a reactant liquid to carry out a chemical reaction, wherein an inner cylinder having a gas collecting section at a lower end, and an outer cylinder having a closed upper end and an open lower end. A gas-liquid contact reactor characterized in that a cylindrical structure having a vertical gas flow path communicating with the inside thereof is provided in a liquid phase portion. 5. A gas-liquid contact reactor for injecting a reactant gas into a reactant liquid to carry out a chemical reaction, the reactor having a vertical gas passage communicating with the inside thereof, and collecting gas at a lower end of the gas passage. A gas-liquid contact reactor characterized in that a structure is provided in a liquid phase portion, the structure being provided with a second gas flow path opened downward. 6. The gas-liquid contact reactor according to claim 1, comprising a plurality of gas returning bodies. 7. The gas-liquid contact reactor according to claim 1, wherein the reaction raw material liquid is liquid sulfur and the reaction raw material gas is hydrogen gas.